The most recent development in special prosecutor Robert Mueller’s investigation into Russia's impact in the 2016 U.S. election was former Donald Trump campaign chair Paul Manafort's cooperation with Mueller’s team.

Last week, Manafort pleaded guilty to some criminal charges. And this morning, President Trump said he believed Manafort would tell the truth and, therefore, he wasn’t concerned.

To learn more about how significant Manafort’s decision is, and what could be next in the investigation, former U.S. Attorney for Arizona Paul Charlton joined The Show.